An Unusual Event was declared at Arkansas’ Nuclear One power plant Tuesday after the transformer to Unit 2 experienced an electrical explosion in the switchyard, causing the unit to shut down. An Unusual Event is declared when an event indicates a potential degradation of the level of safety.
After declaration at the Entergy Operations, Inc. owned facility, the Nuclear Regulatory Commission (NRC) activated its incident response center in Arlington, Texas. NRC's senior resident inspector has been assigned to monitor the control room, keeping Unit 2 offline during the investigation. The cause of the explosion and the necessary repairs has yet to be determined.
An Unusual Event is the lowest of four nuclear emergency categories.
Unit 1 remains operating at about 95 percent power.
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